6 yolks
2 1/2 c. flour
1/2 lb. butter
2 tbsp. sour cream
1 tbsp. vinegar
4 egg whites
3/4 c. sugar
1/2 lb. finely chopped walnuts
1 tbsp. vanilla

Cut butter into flour until real fine. Add egg yolks, sour cream, and vinegar; mix well. Form into 1-inch balls; set aside.

FILLING:

Beat egg whites until frothy; beat and add sugar until stands in peaks. Mix in walnuts and vanilla. Roll out balls; place 1 teaspoon filling across middle of ball.

Roll close into shape of "C". Bake 15 minutes at 350 degrees. Cool and sprinkle with confectioners sugar.